I'm a happy owner of a 755, and am considering an upgrade to the 7500. I have a number of questions that perhaps you folks can help me with: 1) What does "balanced" mean, and why should I care? 2) has anyone done a side-by-side listening of these two amps and can share with me what they heard?

I'm not opposed to wasting (I mean spending) tons of money to upgrade my system, but I want to understand that I will be hearing a significant improvement.

Thanks.